1 /* -*- c-file-style: "linux"; -*-
3 * Copyright (C) 1998-2001 by Andrew Tridgell <tridge@samba.org>
4 * Copyright (C) 2001-2002 by Martin Pool <mbp@samba.org>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 * The socket based protocol for setting up a connection with
37 extern int rsync_port;
38 extern int kludge_around_eof;
39 extern int daemon_over_rsh;
41 extern int sanitize_paths;
42 extern int filesfrom_fd;
43 extern int remote_protocol;
44 extern int protocol_version;
45 extern int io_timeout;
46 extern int orig_umask;
48 extern int default_af_hint;
49 extern char *bind_address;
50 extern struct exclude_list_struct server_exclude_list;
51 extern char *exclude_path_prefix;
52 extern char *config_file;
57 * Run a client connected to an rsyncd. The alternative to this
58 * function for remote-shell connections is do_cmd().
60 * After negotiating which module to use and reading the server's
61 * motd, this hands over to client_run(). Telling the server the
62 * module will cause it to chroot/setuid/etc.
64 * Instead of doing a transfer, the client may at this stage instead
65 * get a listing of remote modules and exit.
67 * @return -1 for error in startup, or the result of client_run().
68 * Either way, it eventually gets passed to exit_cleanup().
70 int start_socket_client(char *host, char *path, int argc, char *argv[])
73 char *p, *user = NULL;
75 /* this is redundant with code in start_inband_exchange(), but
76 * this short-circuits a problem before we open a socket, and
77 * the extra check won't hurt */
79 rprintf(FERROR,"ERROR: The remote path must start with a module name not a /\n");
83 p = strchr(host, '@');
90 fd = open_socket_out_wrapped(host, rsync_port, bind_address,
93 exit_cleanup(RERR_SOCKETIO);
95 ret = start_inband_exchange(user, path, fd, fd, argc);
97 return ret < 0? ret : client_run(fd, fd, -1, argc, argv);
100 int start_inband_exchange(char *user, char *path, int f_in, int f_out, int argc)
103 char *sargs[MAX_ARGS];
105 char line[MAXPATHLEN];
108 if (argc == 0 && !am_sender)
112 rprintf(FERROR, "ERROR: The remote path must start with a module name\n");
117 user = getenv("USER");
119 user = getenv("LOGNAME");
121 /* set daemon_over_rsh to false since we need to build the
122 * true set of args passed through the rsh/ssh connection;
123 * this is a no-op for direct-socket-connection mode */
125 server_options(sargs, &sargc);
127 sargs[sargc++] = ".";
130 sargs[sargc++] = path;
134 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
136 if (!read_line(f_in, line, sizeof line - 1)) {
137 rprintf(FERROR, "rsync: did not see server greeting\n");
141 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
142 /* note that read_line strips of \n or \r */
143 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n",
147 if (protocol_version > remote_protocol)
148 protocol_version = remote_protocol;
150 p = strchr(path,'/');
152 io_printf(f_out, "%s\n", path);
155 /* Old servers may just drop the connection here,
156 rather than sending a proper EXIT command. Yuck. */
157 kludge_around_eof = list_only && (protocol_version < 25);
160 if (!read_line(f_in, line, sizeof line - 1)) {
161 rprintf(FERROR, "rsync: didn't get server startup line\n");
165 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
166 auth_client(f_out, user, line+18);
170 if (strcmp(line,"@RSYNCD: OK") == 0)
173 if (strcmp(line,"@RSYNCD: EXIT") == 0) {
174 /* This is sent by recent versions of the
175 * server to terminate the listing of modules.
176 * We don't want to go on and transfer
177 * anything; just exit. */
181 if (strncmp(line, "@ERROR", 6) == 0) {
182 rprintf(FERROR,"%s\n", line);
183 /* This is always fatal; the server will now
184 * close the socket. */
185 return RERR_STARTCLIENT;
187 rprintf(FINFO,"%s\n", line);
190 kludge_around_eof = False;
192 for (i = 0; i < sargc; i++) {
193 io_printf(f_out, "%s\n", sargs[i]);
195 io_printf(f_out, "\n");
197 if (protocol_version < 23) {
198 if (protocol_version == 22 || !am_sender)
199 io_start_multiplex_in(f_in);
207 static int rsync_module(int f_in, int f_out, int i)
210 char *argv[MAX_ARGS];
212 char line[MAXPATHLEN];
213 uid_t uid = (uid_t)-2; /* canonically "nobody" */
214 gid_t gid = (gid_t)-2;
216 char *addr = client_addr(f_in);
217 char *host = client_name(f_in);
218 char *name = lp_name(i);
219 int use_chroot = lp_use_chroot(i);
222 char *request = NULL;
224 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
225 rprintf(FERROR,"rsync denied on module %s from %s (%s)\n",
227 io_printf(f_out, "@ERROR: access denied to %s from %s (%s)\n",
232 if (am_daemon && am_server) {
233 rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n",
237 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
239 rsyserr(FERROR, errno, "failed to open lock file %s",
241 io_printf(f_out, "@ERROR: failed to open lock file %s\n",
244 rprintf(FERROR,"max connections (%d) reached\n",
245 lp_max_connections(i));
246 io_printf(f_out, "@ERROR: max connections (%d) reached - try again later\n",
247 lp_max_connections(i));
252 auth_user = auth_server(f_in, f_out, i, addr, "@RSYNCD: AUTHREQD ");
255 rprintf(FERROR,"auth failed on module %s from %s (%s)\n",
257 io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
263 am_root = (MY_UID() == 0);
267 if (!name_to_uid(p, &uid)) {
268 if (!isdigit(*(unsigned char *)p)) {
269 rprintf(FERROR,"Invalid uid %s\n", p);
270 io_printf(f_out, "@ERROR: invalid uid %s\n", p);
277 if (!name_to_gid(p, &gid)) {
278 if (!isdigit(*(unsigned char *)p)) {
279 rprintf(FERROR,"Invalid gid %s\n", p);
280 io_printf(f_out, "@ERROR: invalid gid %s\n", p);
287 /* TODO: If we're not root, but the configuration requests
288 * that we change to some uid other than the current one, then
291 /* TODO: Perhaps take a list of gids, and make them into the
292 * supplementary groups. */
294 exclude_path_prefix = use_chroot? "" : lp_path(i);
295 if (*exclude_path_prefix == '/' && !exclude_path_prefix[1])
296 exclude_path_prefix = "";
298 p = lp_include_from(i);
299 add_exclude_file(&server_exclude_list, p,
300 XFLG_FATAL_ERRORS | XFLG_DEF_INCLUDE);
303 add_exclude(&server_exclude_list, p,
304 XFLG_WORD_SPLIT | XFLG_DEF_INCLUDE);
306 p = lp_exclude_from(i);
307 add_exclude_file(&server_exclude_list, p,
311 add_exclude(&server_exclude_list, p, XFLG_WORD_SPLIT);
313 exclude_path_prefix = NULL;
319 * XXX: The 'use chroot' flag is a fairly reliable
320 * source of confusion, because it fails under two
321 * important circumstances: running as non-root,
322 * running on Win32 (or possibly others). On the
323 * other hand, if you are running as root, then it
324 * might be better to always use chroot.
326 * So, perhaps if we can't chroot we should just issue
327 * a warning, unless a "require chroot" flag is set,
328 * in which case we fail.
330 if (chroot(lp_path(i))) {
331 rsyserr(FERROR, errno, "chroot %s failed", lp_path(i));
332 io_printf(f_out, "@ERROR: chroot failed\n");
336 if (!push_dir("/")) {
337 rsyserr(FERROR, errno, "chdir %s failed\n", lp_path(i));
338 io_printf(f_out, "@ERROR: chdir failed\n");
343 if (!push_dir(lp_path(i))) {
344 rsyserr(FERROR, errno, "chdir %s failed\n", lp_path(i));
345 io_printf(f_out, "@ERROR: chdir failed\n");
352 /* XXXX: You could argue that if the daemon is started
353 * by a non-root user and they explicitly specify a
354 * gid, then we should try to change to that gid --
355 * this could be possible if it's already in their
356 * supplementary groups. */
358 /* TODO: Perhaps we need to document that if rsyncd is
359 * started by somebody other than root it will inherit
360 * all their supplementary groups. */
363 rsyserr(FERROR, errno, "setgid %d failed", (int)gid);
364 io_printf(f_out, "@ERROR: setgid failed\n");
367 #ifdef HAVE_SETGROUPS
368 /* Get rid of any supplementary groups this process
369 * might have inheristed. */
370 if (setgroups(1, &gid)) {
371 rsyserr(FERROR, errno, "setgroups failed");
372 io_printf(f_out, "@ERROR: setgroups failed\n");
378 rsyserr(FERROR, errno, "setuid %d failed", (int)uid);
379 io_printf(f_out, "@ERROR: setuid failed\n");
383 am_root = (MY_UID() == 0);
386 io_printf(f_out, "@RSYNCD: OK\n");
388 argv[argc++] = "rsyncd";
391 if (!read_line(f_in, line, sizeof line - 1))
399 if (!(argv[argc] = strdup(p)))
403 if (start_glob == 1) {
407 glob_expand(name, argv, &argc, MAX_ARGS);
411 if (strcmp(line, ".") == 0)
414 if (argc == MAX_ARGS)
419 ret = parse_arguments(&argc, (const char ***) &argp, 0);
421 if (filesfrom_fd == 0)
426 rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n",
427 am_sender ? "on" : "to",
428 request, auth_user, host, addr);
430 rprintf(FLOG, "rsync %s %s from %s (%s)\n",
431 am_sender ? "on" : "to",
432 request, host, addr);
438 /* don't allow the logs to be flooded too fast */
439 if (verbose > lp_max_verbosity())
440 verbose = lp_max_verbosity();
443 if (protocol_version < 23) {
444 if (protocol_version == 22 || am_sender)
445 io_start_multiplex_out(f_out);
448 /* For later protocol versions, we don't start multiplexing
449 * until we've configured nonblocking in start_server. That
450 * means we're in a sticky situation now: there's no way to
451 * convey errors to the client. */
453 /* FIXME: Hold off on reporting option processing errors until
454 * we've set up nonblocking and multiplexed IO and can get the
455 * message back to them. */
458 exit_cleanup(RERR_UNSUPPORTED);
462 io_timeout = lp_timeout(i);
464 start_server(f_in, f_out, argc, argp);
469 /* send a list of available modules to the client. Don't list those
470 with "list = False". */
471 static void send_listing(int fd)
473 int n = lp_numservices();
476 for (i = 0; i < n; i++)
478 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
480 if (protocol_version >= 25)
481 io_printf(fd,"@RSYNCD: EXIT\n");
484 /* this is called when a connection is established to a client
485 and we want to start talking. The setup of the system is done from
487 int start_daemon(int f_in, int f_out)
493 if (!lp_load(config_file, 0))
494 exit_cleanup(RERR_SYNTAX);
499 set_socket_options(f_in, "SO_KEEPALIVE");
500 set_socket_options(f_in, lp_socket_options());
501 set_nonblocking(f_in);
504 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
506 motd = lp_motd_file();
508 FILE *f = fopen(motd,"r");
509 while (f && !feof(f)) {
510 int len = fread(line, 1, sizeof line - 1, f);
513 io_printf(f_out, "%s", line);
518 io_printf(f_out, "\n");
521 if (!read_line(f_in, line, sizeof line - 1))
524 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
525 io_printf(f_out, "@ERROR: protocol startup error\n");
528 if (protocol_version > remote_protocol)
529 protocol_version = remote_protocol;
533 if (!read_line(f_in, line, sizeof line - 1))
536 if (!*line || strcmp(line,"#list") == 0) {
542 /* it's some sort of command that I don't understand */
543 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
549 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
554 return rsync_module(f_in, f_out, i);
558 int daemon_main(void)
562 if (is_a_socket(STDIN_FILENO)) {
565 /* we are running via inetd - close off stdout and
566 * stderr so that library functions (and getopt) don't
567 * try to use them. Redirect them to /dev/null */
568 for (i = 1; i < 3; i++) {
570 open("/dev/null", O_RDWR);
573 return start_daemon(STDIN_FILENO, STDIN_FILENO);
579 if (!lp_load(config_file, 1))
580 exit_cleanup(RERR_SYNTAX);
584 rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n",
585 RSYNC_VERSION, rsync_port);
586 /* TODO: If listening on a particular address, then show that
587 * address too. In fact, why not just do inet_ntop on the
588 * local address??? */
590 if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) {
593 pid_t pid = getpid();
594 cleanup_set_pid(pid);
595 if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC,
596 0666 & ~orig_umask)) == -1) {
598 rsyserr(FLOG, errno, "failed to create pid file %s", pid_file);
599 exit_cleanup(RERR_FILEIO);
601 snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid);
602 write(fd, pidbuf, strlen(pidbuf));
606 start_accept_loop(rsync_port, start_daemon);